How to PXE boot a LiveCD ?

[Sukesh Nischal]

Hi

I'm trying to setup a PXE boot environment to start a LiveCD.

I've setup DHCP/ tftpboot and this has tested fine doing kickstart
installations. Next step is to be able to boot a live cd

Ive created a custom live cd ISO which boots fine from a USB stick.

I then ran livecd-iso-to-pxeboot to generate a tftpboot directory and
merged this with my existing configs.

The problem I'm getting is that the booting stops at 'Cannot open root
device live:/livecd/livecd.iso'

This is the entry I have in /var/lib/tftboot/pxelinux.cfg/default
(amongst other working things)



LABEL livecd
        KERNEL /livecd/vmlinuz0
        APPEND rootflags=loop initrd=/livecd/initrd0.img
root=live:/livecd/livecd.iso debug rootfstype=auto ro liveimg
rd.luks=0 rd.md=0 rd.dm=0


Heres what I have in /var/lib/tftpboot/livecd

# ls -lR /var/lib/tftpboot/livecd/
/var/lib/tftpboot/livecd/:
total 1365096
-rw-r--r-- 1 root root       220 Mar 20 16:58 default
-rw-r--r-- 1 root root 701686594 Mar 20 16:58 initrd0.img
-rw-r--r-- 1 root root     26828 Mar 20 16:58 pxelinux.0
-rw-r--r-- 1 root root 692060160 Mar 20 16:57 livecd.iso
-r--r--r-- 1 root root   4063584 Mar 20 16:58 vmlinuz0


This would be such a useful thing to have working, has anyone actually
got this working? And can anyone see what I'm doing wrong?

[Francesco Frassinelli]

2012/4/3 Sukesh Nischal <sukesh.nischal(a)gmail.com&gt;

>  Hi
>
>  I'm trying to setup a PXE boot environment to start a LiveCD.
>  
Similar discussion:
http://lists.fedoraproject.org/pipermail/livecd/2011-November/006972.html

Hope it could help you
Francesco Frassinelli

[Sukesh Nischal]

Interesting thread, I'm now investigating how this is related to
dracut. Also my problem is that I cannot get this working at all, im
not bothered about initrd sizes (yet!) . Did you manage to get it
working at all? If so, how ?

On 3 April 2012 11:29, Francesco Frassinelli <fraph24(a)gmail.com&gt; wrote:
>  2012/4/3 Sukesh Nischal <sukesh.nischal(a)gmail.com&gt;
> >
> > Hi
> >
> > I'm trying to setup a PXE boot environment to start a LiveCD.
>
>
>  Similar discussion:
>  http://lists.fedoraproject.org/pipermail/livecd/2011-November/006972.html
>
>  Hope it could help you
>  Francesco Frassinelli
>
>  --
>  livecd mailing list
>  livecd(a)lists.fedoraproject.org
>  https://admin.fedoraproject.org/mailman/listinfo/livecd

[Phil Meyer]

On 04/03/2012 04:13 AM, Sukesh Nischal wrote:
>  Hi
>
>  I'm trying to setup a PXE boot environment to start a LiveCD.
>
>  I've setup DHCP/ tftpboot and this has tested fine doing kickstart
>  installations. Next step is to be able to boot a live cd
>
>  Ive created a custom live cd ISO which boots fine from a USB stick.
>
>  I then ran livecd-iso-to-pxeboot to generate a tftpboot directory and
>  merged this with my existing configs.
>
>  The problem I'm getting is that the booting stops at 'Cannot open root
>  device live:/livecd/livecd.iso'
>  
This sounds like you didn't 'name' your version and it is using the 
default name, and not what it really is, or you used the wrong 
compression method.

When making the livecd, you can name it, such as:

livecd-creator --verbose --fslabel=centos_server_kvm 
--compression-type=gzip --cache=/var/tmp/livecache 
--config=http://mirror.fiber.net/ks/centos_server_kvm.ks

You are welcome to examine and comment on my custom kickstart, but the 
trick here is the name.

By using '--fslabel=centos_server_kvm' this works:

livecd-iso-to-pxeboot `pwd`/centos_server_kvm.iso

and produces:

DEFAULT pxeboot
TIMEOUT 20
PROMPT 0
LABEL pxeboot
     KERNEL vmlinuz0
     APPEND rootflags=loop initrd=initrd0.img 
root=live:/centos_server_kvm.iso rootfstype=auto ro liveimg quiet  rhgb 
rd.luks=0 rd.md=0 rd.dm=0
ONERROR LOCALBOOT 0

Note the name change from yours.  I think that by default if no name is 
given, there may be an issue with the defaults: LiveCD vs livecd or 
something silly like that.  So just name it when you roll it up.  Its 
always better to account for assumptions between different apps.

As a side note, if you are using Fedora vs CentOS/RHEL to create the 
livecd, it will default to a compression that the older kernel cannot use.

This may also be the cause of your problem.

Note the '--compression-type=gzip' command line argument.

Between these two issues, you should be golden.

Good Luck!

[Sukesh Nischal]

I pretty much followed your instructions exactly but still no joy :-(

I'm wondering do I need a special initrd to accomplish this or should
this just work? I  was reading about the dracut-network package and
the livenet module. Is this required to make this work?

Also what does live:/centos_server_kvm.iso refer to ? Is a reference
to the ISO as in the initrd file? If so it doesnt appear to be there.

On 6 April 2012 18:08, Phil Meyer <pmeyer(a)themeyerfarm.com&gt; wrote:
>  On 04/03/2012 04:13 AM, Sukesh Nischal wrote:
> >
> > Hi
> >
> > I'm trying to setup a PXE boot environment to start a LiveCD.
> >
> > I've setup DHCP/ tftpboot and this has tested fine doing kickstart
> > installations. Next step is to be able to boot a live cd
> >
> > Ive created a custom live cd ISO which boots fine from a USB stick.
> >
> > I then ran livecd-iso-to-pxeboot to generate a tftpboot directory and
> > merged this with my existing configs.
> >
> > The problem I'm getting is that the booting stops at 'Cannot open root
> > device live:/livecd/livecd.iso'
> >
>
>  This sounds like you didn't 'name' your version and it is using the default
>  name, and not what it really is, or you used the wrong compression method.
>
>  When making the livecd, you can name it, such as:
>
>  livecd-creator --verbose --fslabel=centos_server_kvm --compression-type=gzip
>  --cache=/var/tmp/livecache
>  --config=http://mirror.fiber.net/ks/centos_server_kvm.ks
>
>  You are welcome to examine and comment on my custom kickstart, but the trick
>  here is the name.
>
>  By using '--fslabel=centos_server_kvm' this works:
>
>  livecd-iso-to-pxeboot `pwd`/centos_server_kvm.iso
>
>  and produces:
>
>  DEFAULT pxeboot
>  TIMEOUT 20
>  PROMPT 0
>  LABEL pxeboot
>     KERNEL vmlinuz0
>     APPEND rootflags=loop initrd=initrd0.img root=live:/centos_server_kvm.iso
>  rootfstype=auto ro liveimg quiet  rhgb rd.luks=0 rd.md=0 rd.dm=0
>  ONERROR LOCALBOOT 0
>
>  Note the name change from yours.  I think that by default if no name is
>  given, there may be an issue with the defaults: LiveCD vs livecd or
>  something silly like that.  So just name it when you roll it up.  Its always
>  better to account for assumptions between different apps.
>
>  As a side note, if you are using Fedora vs CentOS/RHEL to create the livecd,
>  it will default to a compression that the older kernel cannot use.
>
>  This may also be the cause of your problem.
>
>  Note the '--compression-type=gzip' command line argument.
>
>  Between these two issues, you should be golden.
>
>  Good Luck!
>  --
>  livecd mailing list
>  livecd(a)lists.fedoraproject.org
>  https://admin.fedoraproject.org/mailman/listinfo/livecd

[Sukesh Nischal]

I just tried your kickstart file on a centos 6.2 box and the resultant
tftpboot files worked just fine in my pxeboot environment. SO I know
my environment is OK and its not any syntax errors. I'm either missing
packages or theres is a problem with the Fedora 16 packages supporting
this method of booting

On 6 April 2012 18:08, Phil Meyer <pmeyer(a)themeyerfarm.com&gt; wrote:
>  On 04/03/2012 04:13 AM, Sukesh Nischal wrote:
> >
> > Hi
> >
> > I'm trying to setup a PXE boot environment to start a LiveCD.
> >
> > I've setup DHCP/ tftpboot and this has tested fine doing kickstart
> > installations. Next step is to be able to boot a live cd
> >
> > Ive created a custom live cd ISO which boots fine from a USB stick.
> >
> > I then ran livecd-iso-to-pxeboot to generate a tftpboot directory and
> > merged this with my existing configs.
> >
> > The problem I'm getting is that the booting stops at 'Cannot open root
> > device live:/livecd/livecd.iso'
> >
>
>  This sounds like you didn't 'name' your version and it is using the default
>  name, and not what it really is, or you used the wrong compression method.
>
>  When making the livecd, you can name it, such as:
>
>  livecd-creator --verbose --fslabel=centos_server_kvm --compression-type=gzip
>  --cache=/var/tmp/livecache
>  --config=http://mirror.fiber.net/ks/centos_server_kvm.ks
>
>  You are welcome to examine and comment on my custom kickstart, but the trick
>  here is the name.
>
>  By using '--fslabel=centos_server_kvm' this works:
>
>  livecd-iso-to-pxeboot `pwd`/centos_server_kvm.iso
>
>  and produces:
>
>  DEFAULT pxeboot
>  TIMEOUT 20
>  PROMPT 0
>  LABEL pxeboot
>     KERNEL vmlinuz0
>     APPEND rootflags=loop initrd=initrd0.img root=live:/centos_server_kvm.iso
>  rootfstype=auto ro liveimg quiet  rhgb rd.luks=0 rd.md=0 rd.dm=0
>  ONERROR LOCALBOOT 0
>
>  Note the name change from yours.  I think that by default if no name is
>  given, there may be an issue with the defaults: LiveCD vs livecd or
>  something silly like that.  So just name it when you roll it up.  Its always
>  better to account for assumptions between different apps.
>
>  As a side note, if you are using Fedora vs CentOS/RHEL to create the livecd,
>  it will default to a compression that the older kernel cannot use.
>
>  This may also be the cause of your problem.
>
>  Note the '--compression-type=gzip' command line argument.
>
>  Between these two issues, you should be golden.
>
>  Good Luck!
>  --
>  livecd mailing list
>  livecd(a)lists.fedoraproject.org
>  https://admin.fedoraproject.org/mailman/listinfo/livecd